A method for controlling deformation of existing structures near frozen communication channels

Abstract

This application discloses a method for controlling deformation of existing structures near frozen communication channels, which is applied to the field of communication channel construction. Through the design of a first freezing curtain and a second freezing curtain, the entire construction is carried out within the bottom tunnel, eliminating the need for top-down drilling from the top soil layer of the tunnel, resulting in minimal construction impact. Simultaneously, the second freezing curtain is used to form a frozen wall around the existing tunnel above, enveloping it. This frozen wall is formed in conjunction with the first freezing curtain, and is then subjected to surrounding frost heave forces, thereby limiting its deformation. Specifically, a frozen wall is formed as shown in the figure and the figure. At this time, deformation is limited due to the uniform frost heave forces on the upper side, effectively controlling the frost heave deformation of the bottom tunnel and the upper tunnel, thereby effectively improving construction efficiency and increasing construction safety.

Description

Technical Field

[0001] The present application relates to the field of connecting channel construction, and in particular to a method for controlling deformation of an existing structure near a frozen connecting channel. Background Art

[0002] With the development of urban underground space, underground structures are becoming deeper and more numerous, and their mutual impact is increasing. It is often necessary to build underground structures near existing structures. The construction of new structures will inevitably affect existing structures, and excessive settlement and deformation will cause damage to existing structures. Deformation or damage to operating subway tunnels has a greater impact, so the deformation requirements for such underground structures are also more stringent.

[0003] The freezing method is a commonly used construction method in urban underground projects and is currently widely used in the construction of subway connecting channel projects. The main difficulty in facing such problems lies in controlling the deformation caused by frost heave and thaw settlement of the existing upper tunnel. Moreover, the closer the distance, the more difficult it is to control. The present invention provides a new solution to such problems.

[0004] Conventional subway connecting channel freezing projects such as Figure 1 As shown in the figure, a frozen wall is formed around the connecting channel, and part of the connecting channel soil is excavated under the protection of the frozen wall, and finally the structure is formed. When there is an operating tunnel above and it is very close to the connecting channel, if the original freezing method is used for construction, that is, Figure 2 As shown, this will cause frost heave and thaw settlement in the tunnel above, resulting in deformation. The existing tunnel may not meet operational deformation requirements or, more seriously, may be damaged due to uneven deformation. Thaw settlement can generally be controlled by forced thawing and grouting, but controlling frost heave is more difficult. To address this problem, we propose a method to control deformation of existing structures near frozen connecting passages. Summary of the Invention

[0005] The purpose of this application is to design a freezing construction method to prevent frost heave deformation of the upper tunnel, so as to solve the problem that the frost heave deformation of the upper tunnel cannot meet the operational deformation requirements or even more seriously causes damage due to uneven deformation. Compared with the existing technology, a method for controlling the deformation of existing structures near the frozen connecting channel is provided, which specifically includes the following steps:

[0006] S1. Drill horizontal freezing holes between the bottom tunnels where the communication channel is required. The horizontal freezing holes are evenly arranged along the outer contour of the communication channel.

[0007] S2. Among the horizontal freezing holes drilled in step S1, select the highest hole position, drill an oblique upward hole along the horizontal freezing hole at the highest hole position, and extend the drilling of an oblique upward oblique freezing hole, with the drilling direction of the oblique freezing hole being tangent to the circumference of the upper tunnel;

[0008] S3, drill a number of temperature measuring holes and pressure relief holes in the direction of the horizontal freezing hole and the inclined freezing hole, and insert horizontal freezing pipes, inclined freezing pipes, temperature measuring holes and pressure relief pipes into the horizontal freezing holes, inclined freezing holes, temperature measuring holes and pressure relief holes respectively;

[0009] S4. Connect the input ends of the horizontal freezing pipe and the inclined freezing pipe to the freezing station system respectively, debug and operate the freezing station system, perform synchronous freezing operations, and form a first freezing curtain and a second freezing curtain;

[0010] S5. During the synchronous freezing operation, adjust the freezing parameters of the inclined freezing holes according to the deformation of the bottom tunnel at any time to control the frost heave deformation of the upper tunnel;

[0011] S6. Under the premise that the frost heave deformation of the bottom tunnel and the upper tunnel meets the design values, the construction of the connecting channel shall be carried out;

[0012] S7. Grouting operation controls the melting and sinking phenomenon of the bottom tunnel and the upper tunnel.

[0013] Through the design of the first and second freezing curtains, the entire construction process takes place within the bottom tunnel, eliminating the need for top-down drilling from the tunnel's top soil layer. This minimizes the impact on construction. Simultaneously, the second freezing curtain forms a frozen wall around the existing tunnel above, enveloping it. This, in conjunction with the frozen wall formed by the first freezing curtain, is now subject to the surrounding frost heave forces, limiting its deformation. This forms the frozen wall as shown in Figure 1 and Figure 2. At this point, deformation is limited due to the uniform frost heave forces above. This effectively controls the frost heave deformation of the bottom and upper tunnels, significantly improving construction efficiency and safety.

[0014] Furthermore, the first freezing curtain has a square curtain structure, and the second freezing curtain has a V-shaped curtain structure in cross section. The freezing temperatures of the first freezing curtain and the second freezing curtain are both no higher than -10°C.

[0015] Furthermore, the opening position error of the horizontal freezing hole is no more than 150 mm, and the maximum allowable spacing between several horizontal freezing holes is 1500 mm.

[0016] Furthermore, the maximum allowable deflection of the inclined freezing hole is 100 mm, and the maximum allowable spacing between several inclined freezing holes is 1000 mm.

[0017] Furthermore, before the synchronous freezing operation in step S4, an insulation layer needs to be laid on the inner wall of the bottom tunnel and the upper tunnel close to the first freezing curtain and the second freezing curtain, and the laying range is 3000MM from the design boundary of the first freezing curtain and the second freezing curtain.

[0018] Furthermore, the horizontal freezing pipe and the inclined freezing pipe both include an outer tube body and an inner tube body sleeved in the outer tube body. Rotating rings are fixed at both ends of the inner tube body. The rotating rings are rotatably connected to the inner wall of the outer tube body through a bearing structure. The outer wall of the inner tube body is provided with an outer spiral sheet, and the inner wall of the inner tube body is provided with an inner spiral sheet.

[0019] Furthermore, when the outer spiral blade and the inner spiral blade rotate along with the inner tube body, the directions of the liquid driven by the outer spiral blade and the inner spiral blade are opposite to each other.

[0020] Furthermore, a connecting piece is provided between two adjacent outer tube bodies, and the connecting piece includes a symmetrically arranged external thread head. Both ends of the outer tube body are provided with an internal thread matching the external thread head. A rotating connecting head is rotatably connected inside the external thread head, and the rotating connecting head matches the end of the inner tube body.

[0021] Furthermore, a second through hole is provided on the external thread head, and a first through hole matching the second through hole is provided on the rotating ring.

[0022] Furthermore, both ends of the rotary connector are tapered, and the ends of the inner tube body are fixed with wear-resistant rubber rings that match the rotary connector.

[0023] Compared with the existing technology, the advantages of this application are:

[0024] (1) The present invention uses the design of the first freezing curtain and the second freezing curtain, and the entire construction is carried out in the bottom tunnel. There is no need to drill holes from the top of the tunnel, which has a small impact on the construction. At the same time, the second freezing curtain is used to form a frozen wall around the existing tunnel above, wrapping it. In conjunction with the frozen wall formed by the first freezing curtain, it is affected by the surrounding frost heave force, thereby limiting its deformation. That is, the frozen wall is formed as shown in Figure 1 and Figure 2. At this time, the upper part is affected by the uniform frost heave force of the surrounding area, so its deformation is limited, thereby effectively controlling the frost heave deformation of the bottom tunnel and the upper tunnel, thereby effectively improving construction efficiency and increasing construction safety.

[0025] (2) Through the mutual cooperation between the inner tube body with inner spiral blades and the outer tube body, driven by the external brine pump, the cold source brine flows in through the gap between the inner tube body and the outer tube body, and forms the hot source brine after completing the heat exchange with the external soil layer. It refluxes from the bottom of the inner tube body from top to top, circulates in sequence, and completes the freezing operation. In this process, the brine pump is used to drive the inner tube body to rotate relative to the outer tube body, and at the same time, the outer spiral blades and the inner spiral blades rotate synchronously, so that the downstream of the cold source brine and the upstream of the hot source brine are both increased in speed, thereby reducing the power consumption of the brine pump and achieving the purpose of energy saving. At the same time, the spiral feeding of the outer spiral blade makes the heat exchange of the cold source brine more uniform, thereby improving the freezing effect of the soil layer.

[0026] (3) Through the design of the connector with an external thread head, a second through hole, and a rotating connector, when two adjacent outer tube bodies are docked, the external thread head on one side of the connector is pre-connected with the internal thread, and then the external thread head on the other side is rotated with the end of the outer tube body to be docked, thereby realizing rapid docking of the two outer tube bodies. At the same time, during the screwing process of the external thread head, the rotating connector automatically docks with the end of the inner tube body and seals the adjacent inner tube bodies. At the same time, the gap between the inner tube body and the outer tube body is connected through a through hole and a second through hole, thereby realizing rapid connection of the freezing pipe and improving the installation efficiency of the freezing pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the conventional communication channel freezing method construction;

[0028] Figure 2 This is a schematic diagram of the conventional connecting channel freezing method construction under the condition of the existing tunnel above;

[0029] Figure 3 This is a cross-sectional diagram of a tunnel constructed using a new freezing method for a connecting passage under the condition of an existing tunnel above.

[0030] Figure 4 This is a cross-sectional diagram of the connecting channel constructed using the new freezing method under the condition of an existing tunnel above.

[0031] Figure 5 This is a cross-sectional diagram of the new freezing method for constructing a connecting passage under the condition of an existing tunnel above.

[0032] Figure 6 This is a schematic diagram of the cross-section hole arrangement of the connecting channel using the new freezing method under the condition of the existing tunnel above;

[0033] Figure 7 This is a schematic structural diagram of the outer tube body proposed in this application;

[0034] Figure 8 This is a schematic diagram of the explosion structure of the outer tube body and the inner tube body proposed in this application;

[0035] Figure 9 A schematic structural diagram of the connector proposed in this application;

[0036] Figure 10 This is a schematic diagram of a partial cross-sectional structure of the connecting piece proposed in this application when connected to the outer tube body;

[0037] Figure 11 This is a schematic diagram of the liquid flow inside and outside the inner tube body proposed in this application.

[0038] Description of the numbers in the figure:

[0039] Connecting channel 1, bottom tunnel 2, first freezing curtain 3, upper tunnel 4, second freezing curtain 5, inclined freezing pipe 6, outer tube body 7, internal thread 71, first rotating part 72, first through hole 721, inner tube body 73, outer spiral sheet 731, inner spiral sheet 732, connecting part 8, external thread head 81, second through hole 82, rotating connecting head 83. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0041] Example 1:

[0042] This application discloses a method for controlling deformation of existing structures near frozen communication channels. Figure 1-6 , specifically including the following steps:

[0043] S1. Drill horizontal freezing holes between the two bottom tunnels where the communication channel 1 is to be set up. The horizontal freezing holes are evenly arranged along the outer contour of the communication channel 1.

[0044] S2. Among the horizontal freezing holes drilled in step S1, select the highest hole position, drill the holes in an oblique upward direction along the horizontal freezing hole at the highest hole position, and extend the drilling of the oblique freezing holes in an oblique upward direction. The drilling direction of the oblique freezing holes is tangent to the circumference of the upper tunnel 4.

[0045] S3, along the horizontal freezing hole, the inclined freezing hole direction drilled a number of temperature measuring holes and pressure relief holes, and the horizontal freezing hole, the inclined freezing hole, the temperature measuring hole and the pressure relief hole correspondingly inserted the horizontal freezing pipe, the inclined freezing pipe 6, the temperature measuring hole and the pressure relief pipe;

[0046] S4, connecting the input ends of the horizontal freezing pipe and the inclined freezing pipe 6 to the freezing station system respectively, debugging and operating the freezing station system, performing synchronous freezing operation, and forming the first freezing curtain 3 and the second freezing curtain 5;

[0047] S5. During the synchronous freezing operation, the freezing parameters of the inclined freezing holes are adjusted at any time according to the deformation of the bottom tunnel 2 to control the frost heave deformation of the upper tunnel 4;

[0048] S6. Under the premise that the frost heave deformation of the bottom tunnel 2 and the upper tunnel 4 meets the design values, the construction of the connecting channel 1 is carried out;

[0049] S7. Grouting operation controls the melting and sinking phenomenon of the bottom tunnel 2 and the upper tunnel 4.

[0050] It should be noted that in this embodiment, the first freezing curtain 3 is a square curtain structure, and the second freezing curtain 5 is a V-shaped curtain structure. The freezing temperatures of the first freezing curtain 3 and the second freezing curtain 5 are not higher than -10°C, the opening position error of the horizontal freezing hole is not more than 150mm, the maximum allowable spacing between several horizontal freezing holes is 1500mm, the maximum allowable deflection of the inclined freezing hole is 100mm, and the maximum allowable spacing between several inclined freezing holes is 1000mm. Before the synchronous freezing operation in step S4, an insulation layer needs to be laid on the inner wall side of the bottom tunnel 2 and the upper tunnel 4 close to the first freezing curtain 3 and the second freezing curtain 5, and the laying range is 3000MM of the design boundary of the first freezing curtain 3 and the second freezing curtain 5.

[0051] The present invention uses the design of the first freezing curtain 3 and the second freezing curtain 5, and the entire construction is carried out in the bottom tunnel 2, without the need for top-down drilling from the top soil layer of the tunnel, which has little impact on the construction. At the same time, the second freezing curtain 5 is used to form a frozen wall around the existing tunnel above, wrapping it, and cooperating with the frozen wall formed by the first freezing curtain 3. At this time, it is affected by the surrounding frost heave force, thereby limiting its deformation. Figure 3 and Figure 4 As shown, a frozen wall is formed. At this time, the upper part is subjected to uniform frost heave force from the surrounding area, so its deformation is limited, thereby effectively controlling the frost heave deformation of the bottom tunnel 2 and the upper tunnel 4, thereby effectively improving construction efficiency and increasing construction safety.

[0052] For further information, see Figure 7-11The horizontal freezing pipe and the inclined freezing pipe 6 both include an outer tube body 7 and an inner tube body 73 sleeved in the outer tube body 7. Rotating rings 72 are fixed at both ends of the inner tube body 73. The rotating rings 72 are rotatably connected to the inner wall of the outer tube body 7 through a bearing structure. The outer wall of the inner tube body 73 is provided with an outer spiral piece 731, and the inner wall of the inner tube body 73 is provided with an inner spiral piece 732. When the outer spiral piece 731 and the inner spiral piece 732 rotate with the inner tube body 73, the two drive the flow of the liquid in opposite directions.

[0053] Through the mutual cooperation between the inner tube body 73 with the inner spiral piece 732 and the outer spiral piece 731 and the outer tube body 7, under the drive of the external brine pump, the cold source brine flows in through the gap between the inner tube body 73 and the outer tube body 7, and forms the hot source brine after completing the heat exchange with the external soil layer. It refluxes from the bottom of the inner tube body 73 from top to top, circulates in sequence, and completes the freezing operation. In this process, the brine pump is used to drive the inner tube body 73 to rotate relative to the outer tube body 7, and at the same time, the outer spiral piece 731 and the inner spiral piece 732 rotate synchronously, so that the downstream of the cold source brine and the upstream of the hot source brine are both increased in speed, thereby reducing the power consumption of the brine pump and achieving the purpose of energy saving. At the same time, the spiral feeding of the outer spiral piece 731 makes the heat exchange of the cold source brine more uniform, thereby improving the freezing effect of the soil layer.

[0054] For details, please refer to Figure 7-11 A connecting piece 8 is provided between two adjacent outer tube bodies 7. The connecting piece 8 includes a symmetrically arranged external thread head 81. Both ends of the outer tube body 7 are provided with an internal thread 71 matching the external thread head 81. A rotating connector 83 is rotatably connected to the external thread head 81. The rotating connector 83 matches the end of the inner tube body 73. A second through hole 82 is provided on the external thread head 81. A first through hole 721 matching the second through hole 82 is provided on the rotating ring 72. The two ends of the rotating connector 83 have a tapered structure, and the end of the inner tube body 73 is fixed with a wear-resistant rubber ring matching the rotating connector 83.

[0055] Through the design of the connector 8 with the external threaded head 81, the second through hole 82, and the rotating connector 83, when two adjacent outer tube bodies 7 are docked, the external threaded head 81 on one side of the connector 8 is pre-connected with the internal thread 71, and then the external threaded head 81 on the other side is rotated with the end of the outer tube body 7 to be docked, thereby realizing rapid docking of the two outer tube bodies 7. At the same time, during the screwing-in process of the external threaded head 81, the rotating connector 83 automatically docks and seals with the end of the inner tube body 73, so that the adjacent inner tube bodies 73 are sealed and connected. At the same time, the gap between the inner tube body 73 and the outer tube body 7 is connected through a through hole 721 and a second through hole 82, thereby realizing rapid connection of the freezing pipe and improving the installation efficiency of the freezing pipe.

[0056] The above is only a preferred specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed in the present application based on the technical solution and its improved ideas, which should be covered by the scope of protection of the present application.

Claims

1. A method for controlling deformation of existing structures near a frozen communication channel, characterized in that: The specific steps include: S1. Drilling horizontal freezing holes between the bottom tunnels (2) where the communication channel (1) is to be set, wherein the horizontal freezing holes are evenly arranged along the outer contour of the communication channel (1); S2, among the horizontal freezing holes drilled in step S1, the highest hole position is selected, and drilling is performed in an oblique upward direction along the horizontal freezing hole at the highest hole position, and an oblique upward inclined freezing hole is drilled, wherein the drilling direction of the inclined freezing hole is tangent to the circumference of the upper tunnel (4); S3, drilling a number of temperature measuring holes and pressure relief holes in the direction of the horizontal freezing hole and the inclined freezing hole, and inserting a horizontal freezing pipe, an inclined freezing pipe (6), a temperature measuring pipe and a pressure relief pipe into the horizontal freezing hole, the inclined freezing hole, the temperature measuring hole and the pressure relief hole respectively; S4, connecting the input ends of the horizontal freezing pipe and the inclined freezing pipe (6) to the freezing station system respectively, debugging and operating the freezing station system, performing synchronous freezing operation, and forming the first freezing curtain (3) and the second freezing curtain (5); S5. During the synchronous freezing operation, the freezing parameters of the inclined freezing holes are adjusted at any time according to the deformation of the bottom tunnel (2) to control the frost heave deformation of the upper tunnel (4); S6. On the premise that the frost heave deformation of the bottom tunnel (2) and the upper tunnel (4) meets the design values, the construction work of the connecting channel (1) is carried out; S7, grouting operation to control the thawing and sinking phenomenon of the bottom tunnel (2) and the upper tunnel (4); the first freezing curtain (3) is a square curtain structure, the second freezing curtain (5) is a V-shaped curtain structure, and the freezing temperature of the first freezing curtain (3) and the second freezing curtain (5) is not higher than -10°C; Before the synchronous freezing operation in step S4, an insulation layer needs to be laid on the inner wall side of the pipe segments of the bottom tunnel (2) and the upper tunnel (4) near the first freezing curtain (3) and the second freezing curtain (5), and the laying range is 3000MM from the design boundary of the first freezing curtain (3) and the second freezing curtain (5); the horizontal freezing pipe and the inclined freezing pipe (6) both include an outer pipe body (7) and an inner pipe body (73) sleeved in the outer pipe body (7), and both ends of the inner pipe body (73) are fixed with a rotating ring (72), and the rotating ring (72) is rotatably connected to the inner wall of the outer pipe body (7) through a bearing structure, and the outer wall of the inner pipe body (73) is provided with an outer spiral sheet (731), and the inner wall of the inner pipe body (73) is provided with an inner spiral sheet (732); the outer spiral sheet (731) and the inner spiral sheet (732) follow the inner pipe body. When the outer tube bodies (73) rotate, the two drive the flow direction of the liquid in opposite directions; a connecting piece (8) is provided between two adjacent outer tube bodies (7), and the connecting piece (8) includes a symmetrically arranged external thread head (81), and both ends of the outer tube body (7) are provided with an internal thread (71) matching the external thread head (81), and a rotating connecting piece (83) is rotatably connected inside the external thread head (81), and the rotating connecting piece (83) matches the end of the inner tube body (73); a second through hole (82) is provided on the external thread head (81), and a first through hole (721) matching the second through hole (82) is provided on the rotating ring (72); the two ends of the rotating connecting piece (83) are tapered structures, and the end of the inner tube body (73) is fixed with a wear-resistant rubber ring matching the rotating connecting piece (83).

2. A method for controlling deformation of existing structures near a frozen communication channel according to claim 1, characterized in that: The opening position error of the horizontal freezing holes is no more than 150 mm, and the maximum allowable spacing between a plurality of the horizontal freezing holes is 1500 mm.

3. The method for controlling deformation of existing structures near a frozen communication channel according to claim 1, characterized in that: The maximum allowable deflection of the inclined freezing hole is 100 mm, and the maximum allowable spacing between a plurality of the inclined freezing holes is 1000 mm.

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